Clooney, Google, U.N. watch Sudan using satellites

People in Sudan's oil-rich south are widely expected to vote to split away and form a new country in the referendum that was part of a 2005 peace deal ending civil war between north and south.

Ahead of the referendum, violence has already flared. Last week, members of the opposition Umma Party said they were beaten and tear-gassed by Sudanese police when they left a meeting to attend a mosque for Friday prayers.

On December 24, Vice President Joe Biden phoned Sudanese Second Vice President Ali Osman Mohmed Taha to express Washington's concern about violence leading up to the vote.

(Reporting by Bob Tourtellotte in Los Angeles; Additional reporting by Lou Charbonneau in New York; Editing by Chris Wilson)